Aqueous composition useful for stabilizing and texturizing dairy products and process for preparing the same

ABSTRACT

The present invention relates to a process for preparing an aqueous composition useful as a stabilizing and texturizing agent in dairy products, the composition obtainable by said process and a food composition comprising a dairy product base and said aqueous composition.

[0001] The present invention relates to a process for preparing anaqueous composition useful as a stabilizing and texturizing agent indairy products, the composition obtainable by said process and a foodcomposition comprising a dairy product base and the aqueous composition.

[0002] In food industry, many dairy products such as soft white cheeseare processed by heat-treatment, homogenization and hot-filling in orderto obtain the packaged dairy product. If the heat-treatment orhot-filling of the dairy product is carried out at temperatures ofhigher than 60° C., textural quality defects, such as a grainy, sandy ormealy mouth-feel, may result due to uncontrolled protein agglomeration.This is a particular problem of low fat/high protein dairy productscontaining less than 10% fat due to a decreased stabilizing effect ofthe fat component. Although dairy products may be packaged in acold-fill process avoiding elevated temperatures, such cold-fillingrequires the use of an aseptic processing system.

[0003] It is known to use stabilizing compositions containinghydrocolloids and starch in order to avoid syneresis in a dairy product,as described in WO 9957996, U.S. Pat. No. 5,614,243 and EP 289096.However, there is still demand for a further improvement of suchcompositions, in particular to be used in processing at elevatedtemperatures.

[0004] Therefore, it is an object of the present invention to provide ameans for reducing or completely preventing uncontrolled proteinagglomeration in protein-containing dairy products during heat-treatmentor hot-filling, so that a dairy product can be produced combining theadvantages of a hot-fill process (shelf-life extension by 1 to 3 months)and a cold-fill process (high quality product texture) without beingforced to use an aseptic processing system.

[0005] This object is solved in the present invention by providing anaqueous composition comprising whey protein concentrate (WPC), starch, afirst hydrocolloid, and a second hydrocolloid, wherein the aqueouscomposition has been heated to a temperature in the range of 60-100° C.for a period (holding time) of 1 to 120 minutes.

[0006] Thus, in one aspect the present invention provides a process forpreparing an aqueous composition, which process comprises heating anaqueous mixture comprising 1.5 to 45 percent by weight (wt. %) of wheyprotein concentrate (WPC), calculated as WPC dry solids, 1 to 15 wt. %of starch, 0.15 to 6 wt. % of a first hydrocolloid, and 0.03 to 3 wt. %of a second hydrocolloid to a temperature in the range of 60 to 100° C.for a period of 1 to 120 minutes.

[0007] Preferably, the aqueous composition comprises 3 to 30 wt. % ofWPC, more preferably 5 to 25 wt. % and most preferably 10 to 20 wt. %.The whey protein concentrate may be any conventional product, and it maybe in the form of a liquid solution, dispersion or dried powder. In casethe whey protein concentrate is used in liquid form, its content in theaqueous composition is calculated on the basis of the dry WPC matter.Furthermore, if it is in liquid (aqueous) form, the aqueous content ofthe WPC may constitute all or part of the aqueous phase of thestabilizing composition.

[0008] The aqueous composition preferably comprises 1.5 to 10 wt. % ofstarch, more preferably 2.5 to 6 wt. %. Any starch or combinationsthereof may be used. Examples for suitable types of starch are waxymaize, corn, pea, wheat and potato.

[0009] The aqueous composition comprises a first hydrocolloid in anamount of 0.15 to 6 wt. %, preferably 0.3 to 3 wt. % and more preferably1 to 2.5 wt. %. As the first hydrocolloid, a gum is preferably used. Anygum conventionally used in the field of food industry may be used, andthe gum is preferably selected from one or more of carob bean gum(locust bean gum), guar gum, gum arabic, xanthan gum and tara bean gum.More preferably, the gum is carob bean gum.

[0010] The aqueous composition comprises a second hydrocolloid in anamount of 0.03 to 3 wt. %, preferably 0.06 to 2.5 wt. %, more preferably0.15 to 1.5 wt. % and most preferably 0.3 to 1 wt. %. As the secondhydrocolloid, a gel-forming heteropolysaccharide is preferably used. Anygel-forming heteropolysaccharide conventionally used in the field offood industry may be used, and preferred examples are carrageenan andagar, more preferably carrageenan. A combination of one or moregel-forming heteropolysaccharides may be used.

[0011] In one particularly preferred embodiment, carob bean gum andcarrageenan are used as the first and second hydrocolloid, respectively.

[0012] The aqueous composition comprises water in at least an amountnecessary to provide a slurry of the components mentioned above. Waterconstitutes the remainder of the aqueous composition of the inventionneeded to accomplish 100 wt. %. It is also possible to includeadditional components in the aqueous composition, such as texturizingand stabilizing components conventionally used in food industry. In thiscase, water also makes up the remainder of the aqueous compositionneeded to accomplish 100 wt. %.

[0013] In the process for preparing the aqueous composition of thepresent invention, a mixture comprising the components above and wateris heated to a temperature in the range of 60 to 100° C. for a period(holding time) of 1 to 120 minutes.

[0014] Preferably, the heat-treatment is carried out at a temperature inthe range of 70 to 95° C., more preferably 80 to 90° C. The duration ofthe heat-treatment is preferably 3 to 60 minutes, more preferably 5 to30 minutes. The heat-treatment may be carried out under atmosphericpressure or increased pressure.

[0015] The aqueous composition obtainable by the process of the presentinvention is useful as a stabilizing and/or texturizing agent dairyproducts. When used in such products, the aqueous composition canprevent uncontrolled protein agglomeration and, therefore, texturalquality defects such as a grainy, sandy and/or mealy mouth-feel. Inparticular, this effect is more prominent in a high protein dairyproduct. In this specification, the term “high protein” means a ratio ofprotein to fat of more than 1. Preferably, the dairy product is also alow fat dairy product. In this specification, the term “low fat” means afat content of less than 10 wt. % fat, based on the final product.Examples for dairy products wherein the aqueous composition in thepresent invention may be preferably used are yogurt, sour milk, creamcheese and soft white cheese.

[0016] In another aspect, the present invention provides a foodcomposition comprising a dairy product base and the aqueous compositionof the present invention. In the food composition of the presentinvention, the dairy product base is present in an amount of 30 to 80wt. % and the aqueous composition is present in an amount of 70 to 20wt. %, each based on the final food composition. Preferably, the contentof dairy product base and aqueous composition in the food composition is45 to 75 wt. % and 55 to 25 wt. %, respectively, more preferably 60 to70 wt. % and 40 to 30 wt. %, respectively.

[0017] Thus, the resulting food composition effectively comprises, in apreferred embodiment, 0.5 to 15 wt. % of WPC (calculated as dry matter),0.3 to 5 wt. % of starch, 0.05 to 2 wt. % of the first hydrocolloid and0.01 to 1 wt. % of the second hydrocolloid. More preferably, the foodcomposition comprises 1 to 10 wt. % of WPC, 0.5 to 3 wt. % of starch,0.1 to 1.0 wt. % of the first hydrocolloid and 0.02 to 0.8 wt. % of thesecond hydrocolloid. Even more preferably, the resulting foodcomposition comprises 2 to 8 wt. % of WPC, 0.8 to 2 wt. % of starch, 0.3to 0.8 wt. % of the first hydrocolloid and 0.05 to 0.5 wt. % of thesecond hydrocolloid.

[0018] Preferred dairy product bases to be used in the food compositionaccording to the invention are bases for yogurt, sour milk, cream cheeseand soft white cheese. In one preferred embodiment of the invention, alow fat and/or high protein dairy product base is used. It is possibleto use one or more dairy product bases in order to obtain desirablecharacteristics of the final dairy product. It is particularly preferredto use one or more soft white cheese bases for obtaining soft whitecheese, and more preferably to use one or more low fat/high protein softwhite cheese bases. In the latter case, a desirable dairy product havinga low fat content and high protein content while still providingexcellent textural quality (mouth-feel) may be obtained.

[0019] The prepared aqueous composition can be blended either batch wiseor inline (continuously) into the protein-containing dairy product baseprior to final processing, e.g. heat-treatment, homogenization andhot-filling.

[0020] The resulting food composition exhibits improved texture and,therefore, mouth-feel, as no uncontrolled or undesired proteinagglomeration occurs during processing, e.g. heat-treatment orhot-filling. This effect is particularly prominent with low fat/highprotein products such as low fat/high protein soft white cheese which isconventionally subjected to a heat-treatment for sterilization andpackaged by hot-filled requiring a temperature of more than 60° C. Thehot-fill process results in a shelf-life extension, usually by 1 to 3months, without being forced to use an aseptic processing system.Furthermore, when using the aqueous composition of the present inventionin a dairy product, a similar or even improved product quality, e.g.smooth product texture, as compared to a cold-fill processing can beaccomplished.

EXAMPLE

[0021] An aqueous composition was prepared by mixing together dried wheyprotein concentrate, starch, carob bean gum, carrageenan and water asset forth in the following table: Percent by weight Percent by weight(in aqueous (in food Component composition) composition) WPC (dry) 14.6 4.8 Starch 6.1 2.0 Carob bean gum 2.1 0.7 Carrageenan 1.2 0.4 Water 76  25.0  (from aqueous composition only)

[0022] The mixture was heated to a temperature of 95° C. for a holdingtime of 15 minutes. Upon cooling, the aqueous composition was blendedwith low fat/high protein soft white cheese base in an amount of 67 wt.% cheese base and 33 wt. % aqueous composition, based on the resultingblend. The blend was heat-treated at 55° C. for 2 minutes, homogenizedand hot-filled at a temperature of 55° C. The resulting low fat/highprotein soft white cheese exhibited a pleasant mouth-feel with notextural quality defects and no occurrence of syneresis.

We claim:
 1. A process for preparing an aqueous composition comprisingheating an aqueous mixture to a temperature in the range of about 60 toabout 100° C. for a period of about 1 to about 120 minutes, the aqueousmixture comprising about 1.5 to about 45 weight percent whey proteinconcentrate, calculated as dried product, about 1 to about 15 weightpercent starch, about 0.15 to about 6 weight percent of a firsthydrocolloid, and about 0.03 to about 3 weight percent of a secondhydrocolloid.
 2. A process according to claim 1, wherein the wheyprotein concentrate is in liquid or powder form.
 3. The processaccording to claim 1, wherein the starch is selected from one or more ofthe group comprising waxy maize starch, corn starch, pea starch, wheatstarch and potato starch.
 4. The process according to claim 1, whereinthe first hydrocolloid is selected from the group comprising one or moregums and the second hydrocolloid is selected from the group comprisingone or more gel-forming heteropolysaccharides.
 5. The process accordingto claim 4, wherein the gum is selected from the group comprising carobbean gum, guar gum, gum arabic, xanthan gum or tara bean gum.
 6. Theprocess according to claim 4, wherein the gel-formingheteropolysaccharide is selected from the group comprising carrageenanor agar.
 7. The process according to claim 4, wherein the process iscarried out under pressure.
 8. An aqueous composition obtainable by theprocess as claimed in claim
 7. 9. Use of the aqueous composition asclaimed in claim 8 as a texturizing and/or stabilizing agent in dairyproducts.
 10. The use according to claim 9, wherein the dairy product isselected from the group comprising yogurt, sour milk, cream cheeses andsoft white cheeses.
 11. The use according to claim 9, wherein the dairyproduct is a low fat dairy product.
 12. The use according to claim 9,wherein the dairy product is a high protein dairy product.
 13. The useaccording to claim 12 wherein the dairy product is low fat/high proteinsoft white cheese.
 14. A food composition comprising a dairy productbase and an aqueous composition as claimed in claim 8 in a ratio, basedon the food composition, of about 30 to about 80 weight percent of thedairy product base and about 70 to about 20 weight percent of theaqueous composition.
 15. The food composition according to claim 14,wherein the dairy product base is selected from the group comprisingbases for yogurt, sour milk, cream cheese and soft white cheese.
 16. Thefood composition according claim 15, wherein the dairy product base is alow fat dairy product base.
 17. The food composition according to claim14, wherein the dairy product base is a high protein dairy product base.18. The food composition according to claim 17 wherein the dairy productbase is low fat/high protein soft white cheese base.